From Viz:
In order to help her father, Chiwa Takanashi agrees to an arranged marriage with the company president Hokuto Mamiya – a man she doesn’t know – at the request of Hokuto’s grandfather. Chiwa believes the arrangement isn’t binding, but her new partner seems to think otherwise. Can two strangers living together find their way to a happy marriage?!

The series Hapi Mari has been licensed, it is not available in Manga Fox.